A religious co-worker that constantly tries to convert you, or berate you for not being the right religion. Or, telling you that you are going to burn for being an atheist.
An atheist co-worker that constantly makes fun of you because of your beliefs. Keeps telling you that you are falling for superstitious nonsense.
Have you had such at your place of work? What did you do? Confront them? Ignore them? Something else?